<PackageReference Include="Newtonsoft.Json" Version="13.0.1" />

Newtonsoft.Json.Schema.Extensions

public static class Extensions

Contains the JSON schema extension methods.

JSON Schema validation has been moved to its own package. See https://www.newtonsoft.com/jsonschema for more details.
namespace Newtonsoft.Json.Schema { public static class Extensions { public static bool IsValid(this JToken source, JsonSchema schema); public static bool IsValid(this JToken source, JsonSchema schema, out IList<string> errorMessages); public static void Validate(this JToken source, JsonSchema schema); public static void Validate(this JToken source, JsonSchema schema, ValidationEventHandler validationEventHandler); } }